Why conspiracy theories are so popular and how our suspicious minds look for big causes for big outcomes

The speed with which conspiracy theories spread can make them seem typically modern. But, Rob Brotherton, the author of a new study on the mind of the ‘truther’, says they are as old as thinking itself and tap into our darkest prejudices.

In the shadows: Conspiracy theorists said this photo of Apollo 11 astronaut Edwin ‘Buzz’ Aldrin standing by the US flag planted on the surface of the Moon on 20 July 1969 was mocked up EPA

Before the victims had been identified, before any group had claimed responsibility – before the blood had been cleaned from the streets – the “truth” about the terror attacks in Paris was already taking shape online. Just hours after the last shots, one YouTube user explained what had happened in a video that has since been viewed more than 110,000 times.

“It was a false flag event aimed at destabilising Europe into New World Order oblivion,” the anonymous man says in narration laid over shaky mobile phone footage of his laptop. The computer displays images of immigration and the Wikipedia entry for subversion. “Friday 13th is not a coincidence! – it’s an occult date of evil Illuminati satanists,” he adds.

As photographs and footage of the attacks emerged, armies of “truthers” went further, describing in dozens of similar videos and on their slick websites how, among other things, the crime scenes had been staged by the intelligence agencies. The fleeing woman filmed dangling from a window at the Bataclan theatre was an actor wearing a harness.

Terror attacks are always fertile ground for conspiracy theories, none more than 9/11, but committed conspiracy theorists find “truth” anywhere. One truther, as conspiracy theorists prefer to be known (many believe that the use of the term “conspiracy theory” is part of a conspiracy theory) was arrested in Connecticut this month after confronting the sister of a teacher who died in the 2012 Sandy Hook school shooting.